Question: Why do we still have a appendix?

Shikha Sharma answered on 7 Nov 2014:

Hi 322bera39,
I suppose appendix has some good function in our body its just researchers are still not sure about the exact function .
As you know appendix is a blind-ended tube connected to the cecum. For years, biologists believed the human appendix is a vestigial organ with no function like tailbone at the end of spine or wisdom teeth. It was considered as a rudimentary organ of our plant eating ancestors and it was believed to help them in breaking down the cellulose in plants.
Few years ago, researchers at Duke University Medical Center mentioned that good bacteria (help in digestion) of human digestive system use appendix as a safe shelter in case of diseases such as cholera or dysentery. In 2011, this theory received more credibility when scientists at Winthrop University Hospital in Mineola, N.Y., observed that the appendix was serving a useful function in patients infected with the bacterium Clostridium difficile (cause infectious diarrhea). They stated that “The Appendix May Protect Against Clostridium difficile Recurrence” the scientists observed that the recurrence of the infection was only 11% in the patients who had an appendix, whereas it was 48% in patients who had their appendix removed. Thus, they also reported that appendix provides a protective shelter to good bacteria when the body’s digestive system needs it most.
I suppose in modern societies, we all follow good sanitation practices and avoid diseases of human digestive system and thus appendix seems to be useless. So, I am really not sure if it is useless or we are still not clear with its function.
I hope in future using new technologies researchers will have a proper answer to our queries regarding appendix.

Shikha